Development of an integrated laboratory air handling unit (LAHU) system for laboratory buildings

This dissertation describes the development and implementation of an integrated air handling unit system for laboratory buildings, called the Laboratory Air Handling Unit (LAHU) system. This system minimizes thermal energy use and improves the office area indoor air quality (IAQ) in laboratory buildings. Theoretical optimal airflow control schedules have been developed, implemented and tested to provide general guidelines for optimal outside air intake and return air distribution within the LAHU system for different weather and building load conditions. Theoretical optimal heat recovery control schedules have also been developed, implemented and tested to provide general guidelines for optimal heat recovery discharge air temperature control. The optimization methodology applied in this study can also be used to solve other linear optimization problems. The dissertation describes and demonstrates the performance of the LAHU system using both theoretical energy analysis and experimental studies of an actual LAHU system implemented and tested in a real occupied university laboratory building. Theoretical energy analysis suggests that the LAHU system can reduce annual energy by 20% to 40%, and introduce up to 100% outside air to the office areas with the optimal airflow control, compared to conventional dedicated AHU systems typically used in laboratory buildings. The optimal heat recovery control of the LAHU can reduce the heat recovery pump power by up to 100% during economizer mode and reduce thermal energy by up to 27% for laboratory buildings in typical climates in the middle-west of the USA. Compared with the conventional AHUs design, preliminary experimental results establish that between 24% and 32% less heating was required by the LAHU system implemented with the optimal outside air and heat recovery control in economizer mode. Further, heat recovery pump operation was reduced by 3,000 hours, or 50% per year. The LAHU is an energy-efficient system for laboratory buildings. We hope that this dissertation and the results reported herein will serve as a guide for the implementation of the LAHU system into building design and operation